Validation of Bedaquiline Phenotypic Drug Susceptibility Testing Methods and Breakpoints: a Multilaboratory, Multicountry Study
Validation of Bedaquiline Phenotypic Drug Susceptibility Testing Methods and Breakpoints: a Multilaboratory, Multicountry Study
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DOI：
10.1128/jcm.01677-19
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发表时间：
2020-04-01
影响因子：
9.4
通讯作者：
Omar, Shaheed, V
中科院分区：
文献类型：
--
作者：
Kaniga, Kone;Aono, Akio;Omar, Shaheed, V
耐药结核病仍然是一个主要的公共卫生问题。除了有效的治疗外，还需要经过验证和标准化的药敏试验（DST）来改善患者护理。这项多国、多实验室的外部质量评估（EQA）研究旨在验证贝达喹啉临时MIC断点和世界卫生组织临时临界浓度（cc）的敏感性、特异性和可重复性，以对临床结核分枝杆菌分离物进行药物敏感/耐药分类。采用三种方法：Middlebrook 7H11琼脂比（AP）法、肉汤微量稀释（BMD）法和分枝杆菌生长指示管（MGIT）法。5个实验室中的每一个在3个时间点检测了40个分离株（20个独特分离株，重复）EQA组。该研究验证了BMD法贝达喹啉MIC敏感性断点为0.12 μ g/ml， MGIT法WHO临时cc为1 μ g/ml， 7H11 AP法为0.25 μ g/ml的敏感性和特异性。AP法、BMD（冷冻或干板）和MGIT960的贝达喹啉浓度分别为0.25、0.12和1 μ g/ml时，观察到的结果和预期结果之间的分类一致性以及正确识别敏感/耐药分离物的敏感性/特异性最高。在这些浓度下，将具有耐药性的分离物错误分类为易感的主要错误率是最低的，并且符合CLSI指南。贝达喹啉分光光度法重复性最高的是MGIT960法和BMD法。这些发现验证了标准化的DST方法和解释性标准的使用，以促进常规表型贝达喹啉DST和监测贝达喹啉耐药性的出现。
Drug-resistant tuberculosis persists as a major public health concern. Alongside efficacious treatments, validated and standardized drug susceptibility testing (DST) is required to improve patient care. This multicountry, multilaboratory external quality assessment (EQA) study aimed to validate the sensitivity, specificity, and reproducibility of provisional bedaquiline MIC breakpoints and World Health Organization interim critical concentrations (CCs) for categorizing clinical Mycobacterium tuberculosis isolates as susceptible/resistant to the drug. Three methods were used: Middlebrook 7H11 agar proportion (AP) assay, broth microdilution (BMD) assay, and mycobacterial growth indicator tube (MGIT) assay. Each of the five laboratories tested the 40-isolate (20 unique isolates, duplicated) EQA panel at three time points. The study validated the sensitivity and specificity of a bedaquiline MIC susceptibility breakpoint of 0.12 mu g/ml for the BMD method and WHO interim CCs of 1 mu g/ml for MGIT and 0.25 mu g/ml for the 7H11 AP methods. Categorical agreements between observed and expected results and sensitivities/specificities for correctly identifying an isolate as susceptible/resistant were highest at the 0.25, 0.12, and 1 mu g/ml bedaquiline concentrations for the AP method, BMD (frozen or dry plates), and MGIT960, respectively. At these concentrations, the very major error rates for erroneously categorizing an isolate as susceptible when it was resistant were the lowest and within CLSI guidelines. The most highly reproducible bedaquiline DST methods were MGIT960 and BMD using dry plates. These findings validate the use of standardized DST methodologies and interpretative criteria to facilitate routine phenotypic bedaquiline DST and to monitor the emergence of bedaquiline resistance.